The two answer words to this flat differ only by their fourth letter - as suggested by the keywords CRISPY and CRIMPY. 

To make a CRISPY note look realistic,

Don't use a ballpoint pen - - - No, be

   artistic! 

Cut characters from magazines and

   papers,

And paste them into rows (don't 

   breathe the vapors).

The more haphazard, CRIMPY type,

   the better.

Then none will know the author of the

   letter.

Answers:

 

CRISPY -   RANSOM

CRIMPY - RANDOM 

 

Credit:

The Enigma 

NPL Magazine

March, 2021

DRAUK